from dataclasses import dataclass
from typing import List, Optional
from datetime import datetime

@dataclass
class OilFacility:
    id: int
    name: str
    facility_type: str  # 'import', 'refinery', 'storage', 'airport'
    region: str
    value: float  # 储量/产能
    latitude: float
    longitude: float
    
@dataclass
class OilSupplyLink:
    source: int  # 源设施ID
    target: int  # 目标设施ID
    transportation: str  # 运输方式: pipeline, railway, road
    
@dataclass
class OilSupplyNetwork:
    nodes: List[OilFacility]
    links: List[OilSupplyLink]
    categories: List[dict] 